AIM: To investigate the effects of melatonin (MT) on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in rat models of colitis.METHODS: Healthy adult Sprague-Dawlay (SD) rats of bo...AIM: To investigate the effects of melatonin (MT) on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in rat models of colitis.METHODS: Healthy adult Sprague-Dawlay (SD) rats of both sexes, weighing 280±30 g, were employed in the present study. The rat models of colitis were induced by either acetic acid or 2,4,6-trinitrobenzene sulfonic acid (TNBS) enemas. The experimental animals were randomly divided into melatonin treatment and model control group that were intracolicly treated daily with melatonin at doses of 2.5, 5.0, 10.0 mg.kg-1 and equal amount of saline respectively from 24 h following induction of colitis in rats inflicted with acetic acid enema and the seventh day in rats with TNBS to the end of study. A normal control group of rats treated with neither acetic acid nor TNBS but saline enema was also included in the study. On the 28th day of the experiment, the rat colon mucosal damage index (CDMI) was calculated, and the colonic prostaglandin E2(PGE2), nitric oxide (NO), as well as the iNOS and COX-2expression were also determined biochemically or immunohistochemically.RESULTS: CDMI increased to 2.87±0.64 and 3.12±1.12respectively in rats treated with acetic acid and TNBS enema,which was in accordance with the significantly elevated colonic NO and PGE2 contents, as well as the up-regulated colonic iNOS and COX-2 expression in both of the two rat models of colitis. With treatment by melatonin at the doses of 5.0 and 10.0 mg@kg-1, CDMI in both models of rat colitis was significantly decreased (P＜0.05-0.01), which accorded synchronously and unanimously with the reduced colonic NO and PGE2 content, as well as the down-regulated expression of colonic iNOS and COX-2.CONCLUSION: Melatonin has a protective effect on colonic injury induced by both acetic acid and TNBS enemas, which is probably via a mechanism of local inhibition of iNOS and COX-2 expression in colonic mucosa.展开更多
Granular cell tumor (GCT) is uncommon in the colon and rectum.Here we report a case of GCT in the transverse colon.A 48-year-old male patient underwent a screening colonoscopy.A yellowish sessile lesion,about 4 mm in ...Granular cell tumor (GCT) is uncommon in the colon and rectum.Here we report a case of GCT in the transverse colon.A 48-year-old male patient underwent a screening colonoscopy.A yellowish sessile lesion,about 4 mm in diameter,was found in the transverse colon.An endoscopic snare resection was performed without complication. Histological examination revealed the tumor consisted of plump neoplastic cells with abundant granular eosinophilic cytoplasm containing acidophilic periodic acid Schiff- positive,diastase-resistant granules.Immunohistochemical analysis showed the tumor cells expressed S-100 protein and neuron-specific enolase.Thus,the resected tumor was diagnosed as a GCT.Since GCTs are usually benign,endoscopic resection constitutes an easy and safe treatment. Colonoscopists should consider the possibility of GCT in the differential diagnosis of submucosal tumors of the colon.展开更多
To investigate the miRNA expression in colonic mucosal biopsies from endoscopically inflamed and non inflamed regions of ulcerative colitis (UC) patients. METHODSColonic mucosal pinch biopsies were analyzed from the i...To investigate the miRNA expression in colonic mucosal biopsies from endoscopically inflamed and non inflamed regions of ulcerative colitis (UC) patients. METHODSColonic mucosal pinch biopsies were analyzed from the inflamed and non inflamed regions of same UC patient. Total RNA was isolated and differential miRNA profiling was done using microarray platform. Quantitative Real Time PCR was performed in colonic biopsies from inflamed (n = 8) and non-inflamed (n = 8) regions of UC and controls (n = 8) to validate the differential expression of miRNA. Potential targets of dysregulated miRNA were identified by using in silico prediction tools and probable role of these miRNA in inflammatory pathways were predicted. RESULTSThe miRNA profile of inflamed colonic mucosa differs significantly from the non-inflamed. Real time PCR analysis showed that some of the miRNA were differentially expressed in the inflamed mucosa as compared to non inflamed mucosa and controls (miR-125b, miR-223, miR-138, and miR-155), while (miR-200a) did not show any significant changes. In contrast to microarray, where miR-378d showed downregulation in the inflamed mucosa, qRT-PCR showed a significant upregulation in the inflamed mucosa as compared to the non inflamed. The in silico prediction analysis revealed that the genes targeted by these miRNAs play role in the major signaling pathways like MAPK pathway, NF-κB signaling pathway, cell adhesion molecules which are all assciated with UC. CONCLUSIONThe present study reports disease specific alteration in the expression of miR-125b, miR-155, miR-223 and miR-138 in UC patients and also predict their biological significance.展开更多
文摘AIM: To investigate the effects of melatonin (MT) on the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in rat models of colitis.METHODS: Healthy adult Sprague-Dawlay (SD) rats of both sexes, weighing 280±30 g, were employed in the present study. The rat models of colitis were induced by either acetic acid or 2,4,6-trinitrobenzene sulfonic acid (TNBS) enemas. The experimental animals were randomly divided into melatonin treatment and model control group that were intracolicly treated daily with melatonin at doses of 2.5, 5.0, 10.0 mg.kg-1 and equal amount of saline respectively from 24 h following induction of colitis in rats inflicted with acetic acid enema and the seventh day in rats with TNBS to the end of study. A normal control group of rats treated with neither acetic acid nor TNBS but saline enema was also included in the study. On the 28th day of the experiment, the rat colon mucosal damage index (CDMI) was calculated, and the colonic prostaglandin E2(PGE2), nitric oxide (NO), as well as the iNOS and COX-2expression were also determined biochemically or immunohistochemically.RESULTS: CDMI increased to 2.87±0.64 and 3.12±1.12respectively in rats treated with acetic acid and TNBS enema,which was in accordance with the significantly elevated colonic NO and PGE2 contents, as well as the up-regulated colonic iNOS and COX-2 expression in both of the two rat models of colitis. With treatment by melatonin at the doses of 5.0 and 10.0 mg@kg-1, CDMI in both models of rat colitis was significantly decreased (P＜0.05-0.01), which accorded synchronously and unanimously with the reduced colonic NO and PGE2 content, as well as the down-regulated expression of colonic iNOS and COX-2.CONCLUSION: Melatonin has a protective effect on colonic injury induced by both acetic acid and TNBS enemas, which is probably via a mechanism of local inhibition of iNOS and COX-2 expression in colonic mucosa.
文摘Granular cell tumor (GCT) is uncommon in the colon and rectum.Here we report a case of GCT in the transverse colon.A 48-year-old male patient underwent a screening colonoscopy.A yellowish sessile lesion,about 4 mm in diameter,was found in the transverse colon.An endoscopic snare resection was performed without complication. Histological examination revealed the tumor consisted of plump neoplastic cells with abundant granular eosinophilic cytoplasm containing acidophilic periodic acid Schiff- positive,diastase-resistant granules.Immunohistochemical analysis showed the tumor cells expressed S-100 protein and neuron-specific enolase.Thus,the resected tumor was diagnosed as a GCT.Since GCTs are usually benign,endoscopic resection constitutes an easy and safe treatment. Colonoscopists should consider the possibility of GCT in the differential diagnosis of submucosal tumors of the colon.
基金Supported by Department of Biotechnology,Ministry of Science and Technology,New Delhi,Government of India vide BT/PR8348/MED/30/1023/2013 to Paul JPURSE grant from the Department of Science and Technology,New Delhi India vide 6(54)SLS/JP/DST PURSE/2015-2016
文摘To investigate the miRNA expression in colonic mucosal biopsies from endoscopically inflamed and non inflamed regions of ulcerative colitis (UC) patients. METHODSColonic mucosal pinch biopsies were analyzed from the inflamed and non inflamed regions of same UC patient. Total RNA was isolated and differential miRNA profiling was done using microarray platform. Quantitative Real Time PCR was performed in colonic biopsies from inflamed (n = 8) and non-inflamed (n = 8) regions of UC and controls (n = 8) to validate the differential expression of miRNA. Potential targets of dysregulated miRNA were identified by using in silico prediction tools and probable role of these miRNA in inflammatory pathways were predicted. RESULTSThe miRNA profile of inflamed colonic mucosa differs significantly from the non-inflamed. Real time PCR analysis showed that some of the miRNA were differentially expressed in the inflamed mucosa as compared to non inflamed mucosa and controls (miR-125b, miR-223, miR-138, and miR-155), while (miR-200a) did not show any significant changes. In contrast to microarray, where miR-378d showed downregulation in the inflamed mucosa, qRT-PCR showed a significant upregulation in the inflamed mucosa as compared to the non inflamed. The in silico prediction analysis revealed that the genes targeted by these miRNAs play role in the major signaling pathways like MAPK pathway, NF-κB signaling pathway, cell adhesion molecules which are all assciated with UC. CONCLUSIONThe present study reports disease specific alteration in the expression of miR-125b, miR-155, miR-223 and miR-138 in UC patients and also predict their biological significance.
